Document Type

Conference Proceeding

Publication Title

Annals of Glaciology

Publication Date

2004

First Page

195

Last Page

200

Volume Number

39

Abstract/ Summary

We track dated firn horizons within 400 MHz short-pulse radar profiles to find the continuous extent over which they can be used as historical benchmarks to study past accumulation rates in West Antarctica. The 30-40 cm pulse resolution compares with the accumulation rates of most areas. We tracked a particular set that varied from 30 to 90 m in depth over a distance of 600 km. The main limitations to continuity are fading at depth, pinching associated with accumulation rate differences within hills and valleys, and artificial fading caused by stacking along dips. The latter two may be overcome through multi-kilometer distances by matching the relative amplitude and spacing of several close horizons, along with their pulse forms and phases. Modeling of reflections from thin layers suggests that the - 37 to - 50 dB range of reflectivity and the pulse waveforms we observed are caused by the numerous thin ice layers observed in core stratigraphy. Constructive interference between reflections from these close, high-density layers can explain the maintenance of reflective strength throughout the depth of the firn despite the effects of compaction. The continuity suggests that these layers formed throughout West Antarctica and possibly into East Antarctica as well.

Citation/Publisher Attribution

Arcone, SA, Spikes, VB, Hamilton, GS, and Mayewski, PA, 2004, Stratigraphic Continuity in 400 Mhz Short-Pulse Radar Profiles of Firn in West Antarctica: Annals of Glaciology, Vol 39, 2005, v. 39, p. 195-200. Available on publisher's site at: http://www.ingentaconnect.com/content/igsoc/agl/2004/00000039/00000001/art00030

Publisher Statement

© Copyright 2004 by the International Glaciological Society

DOI

10.3189/172756404781813925

Version

publisher's version of the published document

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